The epicenter of the tremor, which occurred at 0437 GMT, was located 111 kilometers (69 miles) south of the city Puerto El Triunfo in El Salvador, according to the USGS.[break]
The Pacific Tsunami Warning Center said the quake took place at a depth of 54 kilometers and issued a tsunami warning for all Central American nations and Mexico, though it was not yet known if a tsunami had been generated.
No reports of casualties or damage were immediately available.
The reading was based on the open-ended Moment Magnitude scale used by US seismologists, which measures the area of the fault that ruptured and the total energy released.
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